Chiral damping of magnons

Dae-Yun Kim; Imane Berrai; T. S. Suraj; Yves Roussigne; Shuhan Yang; Mohamed Belmeguenai; Fanrui Hu; Guoyi Shi; Hui Ru Tan; Jifei Huang; Anjan Soumyanarayanan; Kyoung-Whan Kim; Salim Mourad Cherif; Hyunsoo Yang

arXiv · 2409.04713

Chiral damping of magnons

Dae-Yun Kim·Imane Berrai·T. S. Suraj·Yves Roussigne·Shuhan Yang·Mohamed Belmeguenai·Fanrui Hu·Guoyi Shi·Hui Ru Tan·Jifei Huang·Anjan Soumyanarayanan·Kyoung-Whan Kim·Salim Mourad Cherif·Hyunsoo Yang

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Abstract

Chiral magnets have garnered significant interest due to the emergence of unique phenomena prohibited in inversion-symmetric magnets. While the equilibrium characteristics of chiral magnets have been extensively explored through the Dzyaloshinskii-Moriya interaction (DMI), non-equilibrium properties like magnetic damping have received comparatively less attention. We present the inaugural direct observation of chiral damping through Brillouin light scattering (BLS) spectroscopy. Employing BLS spectrum analysis, we independently deduce the Dzyaloshinskii-Moriya interaction (DMI) and chiral damping, extracting them from the frequency shift and linewidth of the spectrum peak, respectively. The resulting linewidths exhibit clear odd symmetry with respect to the magnon wave vector, unambiguously confirming the presence of chiral damping. Our study introduces a novel methodology for quantifying chiral damping, with potential ramifications on diverse nonequilibrium phenomena within chiral magnets.

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Dae-Yun Kim, Imane Berrai, T. S. Suraj, Yves Roussigne, Shuhan Yang, Mohamed Belmeguenai, Fanrui Hu, Guoyi Shi, Hui Ru Tan, Jifei Huang, Anjan Soumyanarayanan, Kyoung-Whan Kim, Salim Mourad Cherif, Hyunsoo Yang. 2024-09-07. Chiral damping of magnons. https://arxiv.org/abs/2409.04713

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